Why are sellers hitting such good stocks?

Currently it seems sellers are going after the stocks of companies with excellent long-term prospects. For example, shares of Gilead have fallen 13% over a one month period while Salesforce.com is down about 7% over the same time.

Yet, the drugs in the Gilead pipeline still show substantial promise and the opportunity facing Salesforce.com remains enormous. The declines don't add up. Fundamentally, these stocks appear sound.

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In the long-run Cramer thinks they are. But in the short-term, there's a problem.

"Individuals can own stocks through hell or high water. Institutions can't," Cramer said. That is, hedge funds are expected to generate returns in any environment.

At first, hedge funds started to sell these stocks because they were winners. This selling was intended to raise funds so money managers could put capital to work more aggressively in other parts of the market.

But the weakness caused other problems.

Pros, who were holding the stocks based on fundamentals, just couldn't continue to hold. "They couldn't take any more pain, and they, too, started throwing out the Gileads and the Salesforce.coms before their gains were wiped out entirely," Cramer added.

The "Mad Money" host draws the phenomenon to your attention because he doesn't want you to doubt the fundamentals in these and other declining stocks that otherwise seem like sound investments.

"If you're an individual investor recognize that there may be nothing wrong with these stocks. If you have to, do some selling to save your sanity, but also recognize the weakness is simply due to the mechanics of money management and nothing more."